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Recurrent episodes of spontaneous subconjunctival hemorrhage in patients with factor XIII Val34Leu mutation
Carlo Incorvaia1, Ciro Costagliola, Francesco Parmeggiani
1Department of Ophthalmology, University of Ferrara, Ferrara, Italy. sbd@dns.unife.it
Purpose:
To report on the occurrence of frequent episodes of spontaneous subconjunctival hemorrhage (SCH) in patients with the Leu 34 allele of the coagulation factor XIII (FXIII), known to be associated with high hemorrhagic risk.
Design:
Observational case series.
Methods:
Five young adults who had suffered from recurrent idiopathic SCH not associated with any recognized ocular and systemic hemorrhagic risk factor were investigated. Accurate anamnestic, ophthalmologic, hematologic, and serologic examinations were performed, together with blood pressure measurements, electrocardiogram (ECG), and 24-hour Holter ECG recordings. FXIII Val34Leu polymorphism was studied by DNA chain polymerase reaction.
Results:
DNA analyses showed that the hemorrhagic mutated Leu34 allele was present in four of our selected patients: two mutated homozygotes (Leu/Leu) and two heterozygotes (Val/Leu). In the last subject this polymorphism was not detected. All the other clinical evaluations did not disclose any significant abnormality.
Conclusions:
The FXIII Val34Leu mutation may be associated with an increased risk for spontaneous episodes of SCH.
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